Ancient Greek Astronomical Calculator

 

Just imagine if you will, the ancient Greeks were able to create what is considered the world's first analog computer. This happened around 2,000 years ago when they created the Antikythera Mechanism which was a hand powered device used to predict astronomical events.

What is quite fascinating about the device is that it is considered one of the most complex pieces of engineering to survive from so long ago. The ancient Greeks used it to predict the position of the sun, moon, planets, and the lunar and solar eclipses.

This device was found in 1901 by sponge divers in a shipwreck dating back to Roman times, in a location near the island of Antikythera. They found a device made out of bronze with 30 bronze gears used in  complex patterns  to determine astronomical events.

Scientists have studied this device since it was discovered but it wasn't until 2005 they were able to determine how it worked after using three  dimensional x-rays combined with surface imaging to create a better picture of how the mechanisms actually predicted eclipses and how it calculated the motion of the moon.  However, it wasn't until earlier this year that scientists were able to understand how the full gearing system in the front worked because only one third of the mechanism survived but it was split into 82 pieces.

Some of the results from the research done in 2005, revealed thousands of text characters hidden inside the fragments or pieces and the text has not been seen in over 2000 years. They found a description the back cover which had a description of the heavenly display complete with planets moving along rings represented by marker beads.  In addition, the largest fragment, Fragment A, showed the features of the bearings, pillars, and blocks while another large fragment, Fragment D, showed a disk, a 63 tooth gear and plate. 

A group of people from UCL in London relied on the description on the back cover to recreate the display.  They also relied on the numbers 462 and 442 from the front cover which seem to represent the planetary cycles for Venus and Saturn and these numbers were quite accurate especially since the classic astronomy of the first 1000 years BC originated in Babylon and there is a question as to how the ancient Greeks, arrived at the accurate values for Venus and Saturn.

So the team used an ancient mathematical method used by the Greeks to derive the length of cycles of Venus and Saturn, and also managed to determine the cycles of all the other planets.  The method was described by philosopher Parmendies with enough detail, the team could use it. Furthermore, they took the evidence from Fragment A and Fragment D to the 462 year cycle for Venus and the 63 tooth gear and plate played an important roll in this.

This lead the team to creating a mechanism for each planet that could be used to calculate new advanced astronomical cycles while minimizing the number of gears in the whole system. This has helped science move one step further to fully understanding the device.  Isn't this impressive?  A device that accurately calculated astronomical entities?  Let me know what you think, I'd love to hear.  Have a great day.